Castleknock Castle

Castleknock Castle is a ruined Norman castle located on the grounds of present-day Castleknock College, Castleknock, Dublin, Ireland.

"The position of the castle is commanding, and its two deep ditches, and the ruins of its massive walls, bespeak its former strength. The Castle itself is thickly clad with ivy, and the entire hill covered with large and spreading trees. The whole is now reserved ground, enclosed with a strong fence. The solemn gloom of the place, its dark winding walks, and the profound silence that reigns around, make it a delightful solitude."

A mound may have preceded the present medieval Norman structure. The polygonal keep was the notable feature of the castle. Attached to it was a large squat building. A curtain wall, interspersed with towers, surrounded the castle. There is a moat or ditch constructed around the castle. Today, the site is surrounded by trees while the ruins are seldom visible from the road except in winter. The earliest extant drawing of the castle by Francis Place also shows it in ruins, but somewhat less dilapidated than at present.

There is also a small mound to the west of Castleknock College buildings known as Windmill Hill. There is a water tower there now which was built originally as an observatory by a previous owner, Simon Guinn.

There is evidence of the site's importance prior to the erection of the castle in the Norman period. An ancient pagan cromlech was discovered. "In the year 1861, an ancient Cromlech, or Druid's altar, was discovered in the interior of the old Castle when digging the grave of the Rev. Thomas Plunket. The workmen, coming on a large flat stone, found it too heavy to remove, and immediately commenced to break it. They succeeded after great difficulty, but on detaching a portion, they found, to their surprise, an empty space beneath, and a human skeleton lying at full length. The head and larger bones were almost perfect, and with them were small heaps of dry, whitish dust. The men not understanding the nature of their discovery, placed the bones a little aside, and continued their work. It was not till the grave was filled up, and it was too late to remedy the evil, that the whole matter came to light. From the description given by different persons who were present, there is no doubt that the discovered grave was one of those ancient Cromlechs, or altar tombs, which were used as burial places for kings or notables during the Pagan times. The skeleton in this case was so old that the admission of air caused a portion of the bones to fall into dust; this accounts for the small heaps of whitish dust which were found with the larger bones."

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Wikipedia